Polyphenols based on isoflavones as inhibitors of Helicobacter pylori urease Original Research Article

Twenty polyphenols were synthesized and evaluated for their effect on Helicobacter pylori urease. Among these compounds, 4-(p-hydroxyphenethyl)pyrogallol (15) (IC50 = 0.03 mM) and 7,8,4′-trihydroxyisoflavone (19) (IC50 = 0.14 mM) showed potent inhibitory activities, and inhibited Helicobacter pylori urease in a time-dependent manner. The structure–activity relationship of these polyphenols revealed: the two ortho hydroxyl groups were essential for inhibitory activity of polyphenol. When the C-ring of isoflavone was broken, the inhibitory activity markedly decreased. As for deoxybenzoin, the carboxyl group was clearly detrimental.